You can apply conditionally, based on the fact that you will attend summer school, and your marks should show that you have a good chance of passing the summer courses successfully. The other option open to you is taking correspondence courses. It would be a heavy work load, along with what you are already doing, but it would help you to catch up.

Congratulations on your acquisition of English. You are far more fluent than many native speakers of English that pop up on this site.

Most of the top colleges would look on early graduation as a good thing. It’s the “regular” state colleges which are most likely to think that he is too immature to be away from home. Virginia Tech falls into the former category. My son went away to high school for his last 2 years because he was accepted into our state’s school of science and mathematics. If kids are that smart, it is always the parents who are more prone to pull back. Only you can judge whether he is mature enough to go away a year early, but it sounds as if he has a life plan. That is a huge plus. One suggestion, let him go through the process. If he gets accepted, you can make a decision then as a family about whether he should accept. If he doesn’t get accepted, he can go to a local college & still be way ahead of the curve.